Dungeon Keeper was one or two multiplayer patches away from becoming a major RTS classic that would've rivaled Starcraft, AoE and C&C, but without a working multiplayer it was doomed to die. Electronic Art's policy has always been to release games that would be fun just long enough to keep playing until the next major EA title gets released that they want you to buy.
Peter Molyneux on the other hand wanted to create something that he would be remembered for. His original idea was to create a game where you can play Good vs Evil, something that he explored in other games such as black and white, but EA didn't want to create an epic game, they wanted a cash grab, they cut the funding for Dungeon Keeper and as a result Bullfrog had to rush the multiplayer mode, they had to completely cut out the hero mode, which would've allowed us to play as the good guys (The Knight, the dwarfs, priests, archers, barbarians, fairies, etc.)
Peter Molyneux was so pissed that he left Bullfrog and EA and founded Lionhead studios immediately after the release of the unfinished game that we know as Dungeon Keeper. Of course after Molyneux (and other Bullfrog employees) left they basically shut down Bullfrog, one of the greatest game developers of the 90s. There is a reason why everyone hates EA like the plague.